3-core and 2-core lighting circuit

faz · Mar 10, 2012

Ok so I haven't done a massive amount of domestic work but I've never seen a circuit like this; It seems (but I've only explored a small section of the circuit) that they've used 3-core & earth from the switch to the ceiling rose (live, switched live, neutral & earth), then twin & earth from the ceiling rose to the next switch on the circuit. From there, again in 3-core & earth up to the ceiling rose and on to the next switch and so on...

It seems pretty fool-proof if you ever want to add anything anywhere but great lengths to go to 'just in case'. Is this a known way of doing things 'back in the day'? Has anyone come across this system before?

Rockingit · Mar 10, 2012

Granted that there are several ways to do lighting circuits, especially when 2 & 3 way switching is involved, but such an elaborate waste of copper sounds more like a DIY job.

Eggster71 · Mar 11, 2012

Rockingit said:
Granted that there are several ways to do lighting circuits, especially when 2 & 3 way switching is involved, but such an elaborate waste of copper sounds more like a DIY job.

Either that or they couldn't be bothered to go to the wholesalers for another drun of twin?

johnboy6083 · Mar 11, 2012

maybe the cicuit used to have something on the switch that required a neutral. I install MK masterseal switches, with indicator lights. We wire a neutral to these, but if somebody later did away with our switch and installed a new one without indicators, then the neutral would be surplus.

ackbarthestar · Mar 11, 2012

I've seen this set up before, or should I say I have done it, allowing the lights to be switched separately using a 2-ganged switch plate, a 3-core up to the first ceiling rose, a connector block taking the 2nd switch line onto the 2nd light.

Why a second 3-core to the 2nd light suggests someone had parked their van away from the installation and it was getting near the end of the day, or perhaps, it was someone who liked the idea of providing a live, switched live and neutral at the switch just in case, not that it would have worked unless the cable was the feed between the 2 3-plate roses, or someone was trying to fathom 2 way lighting through the roses and decided the info provided by the local B&Q outlet was insufficient..... Who knows ?